2 rest-collision.cc -- implement Rest_collision
4 source file of the GNU LilyPond music typesetter
6 (c) 1997--2005 Han-Wen Nienhuys <hanwen@cs.uu.nl>
9 #include "rest-collision.hh"
11 #include <cmath> // ceil.
15 #include "note-column.hh"
17 #include "rhythmic-head.hh"
18 #include "output-def.hh"
20 #include "pointer-group-interface.hh"
21 #include "staff-symbol-referencer.hh"
22 #include "duration.hh"
23 #include "directional-element-interface.hh"
25 MAKE_SCHEME_CALLBACK (Rest_collision, force_shift_callback, 2);
27 Rest_collision::force_shift_callback (SCM element_smob, SCM axis)
29 Grob *them = unsmob_grob (element_smob);
31 assert (scm_to_int (axis) == Y_AXIS);
33 if (Note_column::has_rests (them))
35 Grob *rc = unsmob_grob (them->get_object ("rest-collision"));
37 if (rc && !to_boolean (rc->get_property ("positioning-done")))
39 rc->set_property ("positioning-done", SCM_BOOL_T);
43 return scm_from_double (0.0);
46 MAKE_SCHEME_CALLBACK (Rest_collision, force_shift_callback_rest, 2);
48 Rest_collision::force_shift_callback_rest (SCM rest, SCM axis)
50 Grob *rest_grob = unsmob_grob (rest);
51 assert ((Axis) scm_to_int (axis) == Y_AXIS);
53 Grob *parent = rest_grob->get_parent (X_AXIS);
54 if (Note_column::has_interface (parent))
55 return force_shift_callback (parent->self_scm (), axis);
57 return scm_from_double (0.0);
61 Rest_collision::add_column (Grob *me, Grob *p)
63 me->add_dependency (p);
64 Pointer_group_interface::add_grob (me, ly_symbol2scm ("elements"), p);
67 only add callback for the rests, since we don't move anything
72 p->add_offset_callback (Rest_collision::force_shift_callback_proc, Y_AXIS);
73 p->set_object ("rest-collision", me->self_scm ());
75 Grob *rest = unsmob_grob (p->get_object ("rest"));
78 rest->add_offset_callback (Rest_collision::force_shift_callback_rest_proc,
84 TODO: look at horizontal-shift to determine ordering between rests
85 for more than two voices.
88 Rest_collision::do_shift (Grob *me)
90 extract_grob_set (me, "elements", elts);
92 Link_array<Grob> rests;
93 Link_array<Grob> notes;
95 for (int i = 0; i < elts.size (); i++)
98 if (unsmob_grob (e->get_object ("rest")))
101 Ignore rests under beam.
103 Grob *st = unsmob_grob (e->get_object ("stem"));
104 if (st && unsmob_grob (st->get_object ("beam")))
114 handle rest-rest and rest-note collisions
117 * decide not to print rest if too crowded?
121 no partners to collide with
123 if (rests.size () + notes.size () < 2)
124 return SCM_UNSPECIFIED;
126 Real staff_space = Staff_symbol_referencer::staff_space (me);
134 This is incomplete: in case of an uneven number of rests, the
135 center one should be centered on the staff.
137 Drul_array<Link_array<Grob> > ordered_rests;
138 for (int i = 0; i < rests.size (); i++)
140 Grob *r = Note_column::get_rest (rests[i]);
142 Direction d = get_grob_direction (r);
144 ordered_rests[d].push (rests[i]);
146 rests[d]->warning (_ ("can't resolve rest collision: rest direction not set"));
151 ordered_rests[d].sort (Note_column::shift_compare);
152 while (flip (&d) != LEFT)
157 if (ordered_rests[d].size () < 1)
159 if (ordered_rests[-d].size () > 1)
160 ordered_rests[-d][0]->warning (_ ("too many colliding rests"));
162 return SCM_UNSPECIFIED;
165 while (flip (&d) != LEFT);
167 Grob *common = common_refpoint_of_array (ordered_rests[DOWN], me, Y_AXIS);
168 common = common_refpoint_of_array (ordered_rests[UP], common, Y_AXIS);
171 = (ordered_rests[DOWN].top ()->extent (common, Y_AXIS)[UP]
172 - ordered_rests[UP].top ()->extent (common, Y_AXIS)[DOWN]) / staff_space;
176 int amount_down = (int) ceil (diff / 2);
178 Note_column::translate_rests (ordered_rests[DOWN].top (),
181 Note_column::translate_rests (ordered_rests[UP].top (),
182 2 * int (ceil (diff)));
187 for (int i = ordered_rests[d].size () -1; i-- > 0;)
189 Real last_y = ordered_rests[d][i + 1]->extent (common, Y_AXIS)[d];
190 Real y = ordered_rests[d][i]->extent (common, Y_AXIS)[-d];
192 Real diff = d * ((last_y - y) / staff_space);
194 Note_column::translate_rests (ordered_rests[d][i], d * (int) ceil (diff) * 2);
197 while (flip (&d) != LEFT);
204 if (rests.size () > 1)
205 warning (_ ("too many colliding rests"));
207 Direction dir = CENTER;
209 for (int i = rests.size (); !rcol && i--;)
210 if (Note_column::dir (rests[i]))
212 dir = Note_column::dir (rests[i]);
217 return SCM_UNSPECIFIED;
219 Grob *common = common_refpoint_of_array (notes, rcol, Y_AXIS);
221 Interval restdim = rcol->extent (common, Y_AXIS);
222 if (restdim.is_empty ())
223 return SCM_UNSPECIFIED;
225 Real staff_space = Staff_symbol_referencer::staff_space (rcol);
226 Real minimum_dist = robust_scm2double (me->get_property ("minimum-distance"), 1.0) * staff_space;
229 for (int i = 0; i < notes.size (); i++)
230 notedim.unite (notes[i]->extent (common, Y_AXIS));
233 = minimum_dist + dir * max (notedim[dir] - restdim[-dir], 0.0);
235 int stafflines = Staff_symbol_referencer::line_count (me);
238 programming_error ("no staff line count");
242 // move discretely by half spaces.
243 int discrete_dist = int (ceil (dist / (0.5 * staff_space)));
245 // move by whole spaces inside the staff.
246 if (discrete_dist < stafflines + 1)
247 discrete_dist = int (ceil (discrete_dist / 2.0) * 2.0);
249 Note_column::translate_rests (rcol, dir * discrete_dist);
251 return SCM_UNSPECIFIED;
254 ADD_INTERFACE (Rest_collision, "rest-collision-interface",
255 "Move around ordinary rests (not multi-measure-rests) to avoid "
257 "minimum-distance positioning-done elements");